The way I see it: On the previous page, he talked about a serious issue, while being somewhat… dramatic, I guess, about the matter. Her reaction afterwards shows she didn’t take him seriously. Not on the fact he’s toxic, she aknowledged the danger, but on the way he acted. She brought him down a peg, then reminded him his behaviour, from her standpoint, has been far from being worth falling in love.

Being a Geancanach, a fairy described as a seducer, it ought to hurt a bit.